My boyfriend and I are not very experienced divers and so thought we would do our advanced whilst in Cozumel. We couldn't of made a better decision!
Sergio was so friendly and our diving instructor, Ugo, was very knowledgeable and great to dive with. As there was only the two of receiving the instruction, we managed to get the skills done quickly so we could spend more time enjoying the reef and animals.
I would highly recommend that you use Aquatic Sports; just make sure you book your own package through them rather than having it included with a hotel. We ended up paying more this way (we didn't find out until we got there).